Lawrence Krauss is a renowned theoretical physicist, bestselling author, and celebrated lecturer who has greatly contributed to various areas of physics and cosmology. Krauss’s significant scientific contribution includes the 1995 proposal that most of the Universe’s energy resides in empty space, confirmed in 1999 and awarded a Nobel Prize in 2011. He built top-ranked Physics Graduate Research Programs and created pioneering initiatives like the Center for Education and Research in Cosmology and Astrophysics, and a Masters Program in Physics Entrepreneurship. As a part of his tenure at Arizona State University, he led the Origins Project and podcast, an internationally recognized initiative fostering transdisciplinary workshops and public engagement events on topics like the origins of the universe, human origins, consciousness, and culture.
Krauss’s latest book “The Edge of Knowledge” (in the UK, The Known Unknowns) represents the culmination of Krauss’s quest to unravel the mysteries of the universe. In it, he takes us on an enthralling journey, meandering from the vast reaches of the cosmos to the intricate details of life itself. But this is more than just a voyage through the known; it is an invitation to explore the “unknown unknowns” that await us at the very edge of our comprehension. With “The Edge of Knowledge”, Lawrence Krauss offers more than just a book. He provides a compass for those eager to venture into the uncharted territories of science and an inspiration for all who believe in the power of knowledge to transform our understanding of the universe.
In this interview, I speak to Lawrence Krauss, theoretical physicist, bestselling author, and President of the Origins Project. We discuss some of the biggest questions facing our civilisation including the nature of time, space, and the universe.
Q: What is the power of the phrase, I Don’t Know.
[Lawrence Krauss]: “The phrase ‘I don’t know’ serves as both an invitation and a challenge, a beckoning call to delve into the unknown and piece together the enigmatic puzzle of knowledge. Science, at its core, thrives not on regurgitating established facts but on the exhilaration of unearthing new discoveries. Each day, we strive to comprehend the universe just a fraction more than we did the day before. The key to such progress? Acknowledging the gaps in our understanding and having the courage to confront the unknown – even when that means we might be wrong. My book is a testament to the ‘known unknowns’, but the thrill lies just as much, if not more, in the ‘unknown unknowns’. Yet, for now, such a book would be a scant offering, hinting at the vast potential yet to be explored.”
Q: What got you excited about science?
[Lawrence Krauss]: My fascination began at the age of eleven when I read a book about Galileo. What truly captured my imagination was his audacious courage to accept the universe as it truly was, despite the daunting consequences that loomed over him. This portrayal imbued in me a sense of science as a form of heroism. Although my perception of this heroism has since evolved, it sparked my initial enthusiasm for becoming a scientific explorer.
Moreover, the sheer joy inherent in discovery cannot be understated. Picture Galileo’s awe and wonder when he first peered through his telescope and discovered Jupiter’s moons – a sight that challenged all existing paradigms about our cosmos. It must have been a truly transformative moment.
As scientists, we yearn for such rare and profound instances of enlightenment. I have been fortunate enough to experience such moments a handful of times in my career. Those were the times when I felt like I was truly witnessing the universe as it might truly be, offering a perspective divergent from our preconceived notions.
Q: Is time an illusion? What is time?
[Lawrence Krauss]: While some philosophers and scientists argue that time may be fundamentally illusory, for those of us who operate within its constraints, it remains an all-too-real phenomenon. If you miss your 8:15 AM train to work, the illusory nature of time would be the last thing on your mind. This everyday confrontation with time is likely why it became the cornerstone of my exploration – it is the most personal facet of our existence, more so than even space.
As humans, we experience the passage of time with an inherent bittersweet quality. As Einstein humorously quipped – and I’ve repeated his jest often – if you sit on a hot stove, a minute feels like an hour, but spend an hour in delightful conversation, and it flies by as though it were a mere minute. Time is simultaneously subjective and central to our existence.
Einstein’s revolutionary notion that everyone’s time could differ from our own upended our understanding of the world in a way few theories had before. His second, even more ground-breaking proposal was that time and space are simply different facets of the same reality.
This naturally prompts the question: if I can travel to London and back, why can’t I traverse through time in the same manner – into the future or past? It’s a tantalising concept we’ve all entertained. Indeed, my favourite science fiction narratives are those that revolve around time travel.
[Vikas: Does there have to have been a ‘beginning’?]
[Lawrence Krauss]: When it comes to the vast unknowns of the universe, anything is within the realm of possibility. However, contrastingly, our established knowledge – the facts that have withstood rigorous testing and experimentation – remains steadfast. The discovery of new cosmic truths doesn’t negate our prior understanding. For instance, despite Einstein’s theory of relativity extending beyond the scope of Newton’s laws, the latter will remain as valid a million years from now as they are today.
In principle, we could imagine universes that exist infinitely in time. However, as per our current understanding of physics, it appears time itself had a beginning. Yet, when we delve back to the very inception of our universe – the Big Bang, where quantum mechanics and gravity intertwine – we hit the limits of our theoretical framework. Therefore, our conclusions are built upon an incomplete theory, and we acknowledge the presence of certain gaps.
The recognition of a potential multiverse suggests that while our universe, our Big Bang, had a beginning, there could be many other universes that predate ours. Alternatively, it could be that our universe is the only one in existence. If that’s the case, the question of ‘what occurred before the Big Bang?’ is flawed. There was no ‘before’ if time originated at the Big Bang. It’s as illogical as questioning the color of love – we can certainly pose the question, but it lacks any sensible foundation.
Q: Are we reaching the point where our scientific discoveries are beyond our comprehension?
[Lawrence Krauss]: Indeed, these concepts transcend our natural intuition, but I firmly believe they aren’t beyond our grasp. As Einstein marveled, the universe seems to be comprehensible. Take quantum mechanics, for example; it’s intricate and puzzling, and as I often emphasize, it remains a mystery in many respects. Yet, astonishingly, we understand how it functions. It’s quite remarkable that we, creatures who evolved dodging predators on the African savannah, have been able to develop quantum mechanics. I find this to be a splendid evolutionary offshoot.
However, your implication holds true; as science progresses, the frontier of our understanding extends further beyond the bounds of our personal experiences. This expansion often renders physics intimidating to many, as we grapple with concepts such as the inception of the universe, the nature of elementary particles, or the universe’s future.
This might be why biology feels more approachable to people, as it correlates directly to our immediate experiences. But let’s not forget that the vanguard of biology is equally exhilarating. That said, the ultimate mystery, as I argue towards the end of my book, lies within consciousness itself. Despite being an immediate part of our existence, it’s potentially the most complex and elusive aspect of the universe. We haven’t even begun to formulate the right questions to unravel its intricacies. In this regard, consciousness poses an intriguing paradox: while it feels intuitively familiar, it remains the most elusive.
[Vikas: Are we getting any closer- therefore- to understanding consciousness?]
[Lawrence Krauss]: Indeed, there are physicists who posit that quantum mechanics might be pertinent to understanding consciousness, though this link has not yet been definitively established. What we have managed to gather is a vast repository of knowledge about the brain’s functioning and the roles of its various parts. However, when it comes to defining consciousness, we remain largely in the dark, and it may forever elude us.
In a recent dialogue with my friend Noam Chomsky, he proposed that we might be approaching consciousness from the wrong angle, focusing on a misguided notion. Yet, what we can say for certain is that consciousness differs from concepts like gravity in that it’s something we fabricate.
Is it an illusion? Just as some argue that the self or time are illusions, there are those who view consciousness in the same light. To them, I offer the same response: so, what? The real question lies in how this illusion comes into being. When you feel physical pain or emotional heartache, your sense of self assumes utmost importance. Hence, it feels inadequate to simply dismiss this self as illusory.
Unlike gravity, which continues to exert its force on you even in death, consciousness ceases to exist when you pass away. It’s an intriguing distinction, a testament to the complexity of this topic.
Q: How will civilisation change as we answer some of these huge questions?
[Lawrence Krauss]: …the future holds mysteries. When smartphones first emerged, it’s doubtful that anyone could have accurately predicted how radically they would transform our lives in just a decade. I often quip that the only predictions I make are about two trillion years into the future. However, it’s undeniable that each scientific discovery alters our self-perception, and in ways that aren’t always fully appreciated. Science, akin to art, music, and literature, reshapes our perspectives, offering new insights into ourselves and our surrounding universe. This transformative aspect is what makes science as thrilling as any other facet of human culture.
Sure, science gives birth to new technologies, leading some to question its value if it doesn’t immediately spawn innovative tech. To those individuals, I’d respond by asking about the worth of a Mozart symphony. Predicting how science will shape the future is challenging and can even induce fear. The emerging field of artificial intelligence, or AI, stirs anxiety in many who fear it could drastically alter our world. Yet, in the final section of my book, I strive to offer a different perspective on this, suggesting that perhaps these changes aren’t as alarming as they seem.
Yes, AI will change the world, but so did automobiles, fire, and even the very concepts of freedom and liberty. Every intellectual development has altered our way of life, sometimes for better, sometimes for worse. We might not always have control over these changes. The development of nuclear physics, for instance, has resulted in both immense fear and enormous potential, like the promise of nuclear power.
As we navigate these changes, we do have some control. I concluded my previous book with a quote from Louis Pasteur: “Fortune favours the prepared mind.” This sentiment echoes through this current book as well. By exploring the unknown, we prepare ourselves, getting us closer to the cutting edge of science and, possibly, readying us for the next giant leap.
Q: Why is there anything?
[Lawrence Krauss]: The questions “why is there something rather than nothing?” and “the universe for nothing” may not be as distinct as they initially appear. Some have taken issue with my definitions of ‘nothing’ and ‘something’ in these discussions, contending that science has altered these terms. However, I view this evolution of understanding as part of the learning process.
There’s no denying a certain sense of insignificance when contemplating our place in the cosmos. And this feeling is justified – in a cosmic context, we are indeed insignificant. Yet, there’s a complementary perspective that lends us tremendous significance. What if we are the only lifeforms in the universe? While I find this unlikely, if it were true, it would highlight our extraordinary fortune.
Even though we might be cosmically insignificant, our personal significance is vast. The ability to question, to gaze at the night sky, to ponder the stars in wonder – these are fortunate accidents that make us incredibly precious. In fact, I believe we are more precious than we would have been if the universe were specifically designed for us.
Q: Do you think we are alone in the universe?
[Lawrence Krauss]: The query about the origin of life is likely one of the most ripe for resolution among the questions I discuss. While it’s tough to predict with certainty, I believe it’s plausible that, given the array of new tools we now have for observing the universe and investigating the genesis and evolution of life on Earth, we could uncover evidence of life elsewhere in the cosmos within the next few decades. By this, I don’t mean sentient, intelligent life forms, but rather, microbial life.
There’s also a reasonable chance that we’ll grasp how life first appeared on Earth in the next several decades—an astonishing question indeed. I’ve debated this with my friend Richard Dawkins, who questioned whether we’d be able to definitively prove it. The likely answer is no, but if we can devise a scenario so credible that it seems undeniably feasible, we’ll have found at least one plausible route for how chemistry transforms into biology. This transformation represents a fascinating moment when something becomes alive, when you could first label it as ‘living’.
In the book, I invite readers to ponder their own definitions of life, and they might just be surprised at what they discover.
Q: How does science interact with the theological concept of truth?
[Lawrence Krauss]: Let’s take a step back and remember that science can disprove things, but it can’t establish absolute truth. Truths in science are always conditional, limited to a certain range of time and space. However, the tendency is to invoke God as a placeholder whenever we encounter something we don’t understand and don’t wish to probe further.
The true distinction lies in that science never opts to halt its inquiry. There’s a cartoon by Sidney Harris I enjoy that depicts two scientists with a complex equation on a chalkboard. In the middle, it simply says, “and then a miracle occurred.” Science insists on more specificity.
The assumption in science is that if we continue to probe, we’ll figure out the how, and that ‘why’ questions are ultimately about ‘how.’ It’s indeed remarkable, even if some view it as a disaster, that when we’ve asked these questions, we’ve found plausible natural explanations for things that initially appeared miraculous.
A great example of this is Charles Darwin’s work on the diversity of life on Earth. The concept of natural selection, combined with the diversity of genetic information in a population, implies evolution as a necessity. It’s astonishing that no divine intervention is needed. While some might find this disappointing, I personally find it incredibly fascinating.
Q: How resolved is our understanding of space?
[Lawrence Krauss]: In the world of theoretical science, we have theories that are settled and those that are yet to be confirmed. For instance, the notion that space warps in the presence of matter and energy is a settled concept. We can demonstrate this experimentally. General relativity is a robust theory within our own scales, but it falters when we shrink down to minute scales. Efforts to rectify this, essential to understanding the universe on larger scales, often bring us to unproven theories.
Take string theory, for example. It remains a theoretical concept, primarily explored through mathematical frameworks. Despite the compelling motivations behind it, there is yet to be concrete evidence that it accurately represents our universe. But this is the nature of the game, pushing the boundary of knowledge, exploring the unknown.
String theory’s suggestion of additional dimensions is fascinating. The critical question for scientists, of course, is how we might investigate these extra dimensions if they indeed exist. Generally, our ability to probe extra dimensions is limited, perhaps only achievable through the subtle effects of gravity.
Inflation theory posits not extra dimensions, but countless other universes existing in regions of space unreachable by us. It may seem like pure metaphysics. Yet, as a physicist, I’ve shown that certain measurements can indirectly support the existence of these universes, even if direct empirical observation remains out of reach.
This is reminiscent of our history with atoms. In 1905, many chemists regarded atoms as useful conceptual tools for understanding chemistry. Einstein, however, in his PhD thesis, showed a way to verify their existence. Within a few years, the physical reality of atoms was indisputable, even though you couldn’t observe them directly. Maybe, in time, multiverses will become a similarly accepted reality.
[Vikas: … just like quantum computing! Which on the face of it seems like a nonsense!]
[Lawrence Krauss]: …quantum mechanics might seem absurd from a traditional standpoint. As I discuss in the book, quantum mechanics often gets misrepresented, leading to misconceptions that amplify its oddness. Quantum mechanics is indeed stranger than one can fathom. However, this doesn’t reflect on the theory itself but rather on the limits of our imagination.
You’re absolutely correct that even the most arcane physics concepts eventually find their way into our everyday technology. And it’s not just quantum computing. Take my smartphone for example. The functioning of its transistors relies fundamentally on quantum mechanics. In fact, virtually everything we use today has a basis in quantum mechanics.
Moreover, if you thought our earlier discussion about time seemed too abstract, consider this practical application. The operation of GPS satellites, which you might use to find your way home at night, is critically dependent on general relativity. Without our understanding of general relativity, GPS would fail to function accurately, and you could lose your way home in just an hour.
Q: What do you hope your legacy will be?
[Lawrence Krauss]: I tend not to focus on the concept of a legacy, as I don’t find it especially beneficial. My aim is simply to pursue what I can do next that will be of value. My hope is that through my scientific work, writing, and other endeavours, I’ve made a positive impact. I receive messages from people suggesting that I have, which is encouraging. However, my primary goal is to share my own passion.
To paraphrase Carl Sagan: when you’re in love, you want to tell the world about it. My love is for science, and I feel an urge to share it with the world. Yet there’s a bittersweet sentiment to it too; it’s unfortunate that so many people have limited knowledge about science – such an immense part of the human experience – and close themselves off from it. It’s akin to people who have never heard or appreciated music.
My mission, therefore, is to offer people the chance to partake in this extraordinary aspect of being human: asking questions about the universe and discovering that the universe’s imagination far surpasses our own.
The objective of science and education is to challenge us, to put us in a state of unease. Unfortunately, in our contemporary society, many believe that discomfort has no place in education. However, the very essence of learning is to step out of your comfort zone. If you’re never uncomfortable, you’re not testing your boundaries. Living without pushing those limits confines you to a bubble. Yes, you can exist within that bubble, but imagine the astounding aspects of the world that you miss out on!